DANGER
Explosion Hazard . During bypass switching, the
regulator must be in the neutral position . Prior to
bypass switchinge: 1) The regulator must be placed in
the neutral position; 2) Tap-changer operation must be
disabled during the bypass switching . If the regulator is
in any other position, part of the series winding will be
shorted when the bypass switch is closed, resulting in
high circulating current . Failure to comply will result in
death or severe personal injury and equipment damage .
6. Confirm the voltage regulator has been placed in
neutral before proceeding by observing these four
indicators:
a. Neutral light is illuminated continuously and
brightly.
b. Tap-position indication on the control at FC 12
displays 0 for neutral.
c. Position indicator dial pointer is pointing directly at
N or 0 for neutral.
d. Measure the voltage difference between the S and
L bushings. On a de-energized voltage regulator,
this can be done by applying a low voltage (for
example 120 Vac) between the S and SL bushings.
The measured voltage between the S and L
bushings should be zero or very close to zero.
otee:
N
One step off of neutral with a 120 Vac input
would be a 0.75 volts between S and L.
7. Remove the voltage from external source terminals.
8. With regulator in the neutral position, set CONTROL
FUNCTION switch to
OFF
, set POWER switch to
OFF
,
and remove 6 A motor fuse.
9. For Delta applications only: Close source-load (SL)
disconnect switch.
10. Close regulator bypass-disconnect switch. The regulator
is now energized.
11. Replace 6 A motor fuse, close
V1
knife switch (and
V2
,
V6
, and
V8
if present), open
C
knife switch, and set
POWER switch to
INTERNAL
.
12. Refer to
S
ervice Information MN225003EN,
CL-7
Voltage Regulator Control Installation, Operation, and
Maintenance Instructions
, for information on the CL-7
voltage regulator control, including placing the control
into service and initial programming.
Setting the manual (hard) limit switches
otee:
N
Refer to
“Position indicator and ADD-AMP
on page 13 for a complete discussion
of these features.
Before setting the manual limit switches, be sure the new
settings will not conflict with the present tap-changer
position; see
. Do not set the switches below the
indicated tap-changer position. For example, if the main
hand is at step 12 and the change to be made is from plus
or minus 10% (step 16) to plus or minus 5% (step 8), run
the tap-changer back to step 7 or less, manually. Then set
the limit switches for plus or minus 5% regulation.
Limit switches should be set in anticipation of the
maximum deviation of primary voltage. For example, on
a circuit where 7200 V is to be maintained, plus or minus
10% will permit voltages between 6480 V and 7920 V to
be regulated effectively. For voltages outside this range,
the regulator will not be able to return the voltage to the
preselected level (7200 V). Five percent regulation would
accommodate circuit voltages between 6840 and 7560 V,
maintaining 7200 V for all voltages in this range.
To set the limit switches:
1. Unlatch the captive bezel and swing the cover open.
2. Lift the limit-switch adjustment lever free of the detent
and slide it to the new setting allowing the lever to
snap into the detent stop.
otee:
N
If the ADD-AMP limits have been programmed
into the control (Soft ADD-AMP) and the limit
switches have not been set, it is possible to
manually step the tap-changer beyond the Soft
ADD-AMP limit. If the unit is switched back
to automatic mode, the control will step the
regulator back to within the Soft ADD-AMP limits
as set in the control.
Figure 13 . Position indicator
10
VR-32 and EVER-Tap™ Voltage Regulator
InstallatIon, operatIon, and MaIntenance InstructIons
MN225008EN June 2020
